Organic EL device and method for manufacturing the same

ABSTRACT

An organic EL device includes a thin film transistor (TFT) array substrate including a first insulating substrate, a TFT formed on the first insulating substrate and a capacitor; and an organic EL substrate including a second insulating substrate, and a transparent electrode, an organic EL layer and a metal electrode, which are sequentially stacked on the second insulating substrate; wherein the TFT is electrically connected to the metal electrode.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the invention

[0002] The present invention relates to an organic EL device and amethod of manufacturing the same.

[0003] 2. Description of Related Art

[0004] Recently, in organic EL devices, active matrix organic lightemitting diodes (AM-OLED) that can individually control respectivepixels are widely used. Each of the pixels typically includes a firstthin film transistor (TFT) and a second TFT formed on a transparentsubstrate, a transparent lower electrode electrically connected to astorage capacitor and a drain electrode of the second TFT, an organic ELregion formed on the lower electrode to emit light having apredetermined wavelength, and an opaque upper electrode formed of amaterial such as aluminum over the whole surface of the transparentsubstrate.

[0005] At this point, let us define the AM-OLED that emits light througha back surface of the organic EL region due to the opaque upperelectrode as a “back surface emitting AM-OLED.” A surface through whichlight emits as a “back surface” and a surface through which light doesnot emit is defined as a “front surface.”

[0006] Meanwhile, in the back surface emitting AM-OLED, the pixel areais mostly occupied by the first and second TFT and the storagecapacitor. Therefore, light emitted from just about 20% of total pixelarea is directed toward observers. In other words, the back surfaceemitting AM-OLED has an aperture ratio of about 20%. It makes itdifficult to achieve a high luminance. More current has to be applied,in order to increase brightness in a low aperture ratio device. Thisincreases power consumption, which is unsuitable for portable displaydevices.

[0007] In order to overcome the problems, the AM-OLED should have afront surface emitting structure which light is emitted through thefront surface. In the front surface emitting AM-OLED, the lowerelectrode should be made of an opaque material, and the upper electrodeshould be made of a transparent material.

[0008] However, if the transparent upper electrode is formed on theorganic EL region, the relatively high temperature required fordepositing the transparent upper electrode damages, the organic ELregion. Therefore, it is very difficult to produce a front surfaceemitting AM-OLED.

[0009] U.S. Pat. No. 6,046,543 to Bulovic, et al., entitled “highreliability, high efficiency, integratable organic light emittingdevices and methods of producing same,” describes a method of forming atransparent cathode electrode in order to implement the front surfaceemitting AM-OLED. U.S. Pat. No. 5,981,306 to Burrows, et al., entitled“method for depositing indium tin oxide layers in organic light emittingdevices,” describes a method of forming indium tin oxide (ITO) at a verylow depositing rate in order to implement the front surface emittingAM-OLED. U.S. Pat. No. 5,739,545 to Guha, et al., entitled “organiclight emitting diodes having transparent cathode structures,” describesthe front surface emitting AM-OLED implemented using a transparentcathode electrode.

[0010] However, such methods are not easy to implement, and demand along processing time. In addition, it is difficult to control devicecharacteristics. Besides, in the conventional AM-OLED, as describedabove, the metal can is used to protect the organic EL region fromoxygen and moisture, thus increasing the weight and volume of theAM-OLED as a whole.

SUMMARY OF THE INVENTION

[0011] To overcome the problems described above, preferred embodimentsof the present invention provide an organic EL device having a highaperture ratio, a high brightness, and consuming less power.

[0012] It is another object of the present invention to provide anorganic EL device having a high reliability and a lightweight.

[0013] In order to achieve the above object, the preferred embodimentsof the present invention provide an organic EL device, comprising: athin film transistor (TFT) array substrate including a first insulatingsubstrate, a TFT and a capacitor formed on the first insulatingsubstrate; and an organic EL substrate including a second insulatingsubstrate, and a transparent electrode, an organic EL layer and a metalelectrode, which are sequentially stacked on the second insulatingsubstrate; wherein the TFT is electrically connected to the metalelectrode.

[0014] The TFT array substrate further includes a conductive interfacepad connected to the TFT, the conductive interface pad directlycontacting the metal electrode of the organic EL substrate. The organicEL substrate further includes a protection film for shielding oxygen andmoisture externally coming into. The protection film is formed byrepeatedly depositing a SiNx layer and a SiO₂ layer at least one time.The TFT array substrate and the organic EL substate are sealed by aUV-curable agent. The TFT array substrate further includes a conductiveinterface pad connected to the TFT and a conductive bump pad formed onthe conductive interface pad, the conductive bump pad contacting themetal electrode of the organic EL substrate by a conductive bondingagent. The conductive bonding agent is an anisotropic conductive film(ACF). The anisotropic conductive film also shields off the externaloxygen and moisture. The TFT array substrate further includes aconductive interface pad and a conductive bump pad formed on theconductive interface pad, and the organic EL substrate further includesa polymer bump, wherein the conductive bump pad contacts a portion ofthe metal electrode corresponding to the polymer bump by a conductivebonding agent.

[0015] The preferred embodiments of the present invention furtherprovide a method of manufacturing an organic EL device, comprising:forming a thin film transistor (TFT) array substrate including a TFT anda capacitor formed on a first insulating substrate; forming an orgnaicEL substrate including a transparent electrode, an organic EL layer anda metal electrode sequentially formed on a second insulating substrate;and sealing the TFT array substrate and the organic EL substrate toelectrically connect the TFT of the TFT array substrate to the metalelectrode of the organic EL substrate.

[0016] Using a method of manufacturing the organic EL device accordingto the preferred embodiments of the present invention, an organic ELdevice having a high aperture ratio, a high luminance, and a low powerconsumption can be obtained. In addition, an organic EL device having ahigh reliability and a lightweight can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] For a more complete understanding of the present invention andthe advantages thereof, reference is now made to the followingdescriptions taken in conjunction with the accompanying drawings, inwhich like reference numerals denote like parts:

[0018]FIGS. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16 areprocessing views illustrating a process of manufacturing a thin filmtransistor (TFT) array substrate according to a first preferredembodiment of the present invention;

[0019]FIG. 17 is a cross-sectional view illustrating an organic ELsubstrate according to the first preferred embodiment of the presentinvention;

[0020]FIG. 18 is a cross-sectional view illustrating an organic ELdevice according to the first preferred embodiment of the presentinvention;

[0021]FIG. 19 is a circuit diagram illustrating an equivalent circuit ofone pixel of the organic EL device according to the preferredembodiments of the present invention;

[0022]FIG. 20 is a cross-sectional view illustrating a process ofassembling the organic EL device according to the first preferredembodiment of the present invention;

[0023]FIG. 21 is a perspective view illustrating a TFT array substrateaccording to a second preferred embodiment of the present invention;

[0024]FIGS. 22, 23, 24 and 25 are cross-sectional views illustrating aprocess of manufacturing an organic EL substrate according to the secondpreferred embodiment of the present invention;

[0025]FIGS. 26 and 27 are cross-sectional views illustrating a processof assembling the TFT array substrate and the organic EL substrateaccording to the second preferred embodiment of the present invention;

[0026]FIGS. 28, 29 and 30 are cross-sectional views illustrating aprocess of manufacturing an organic EL substrate according to a thirdpreferred embodiment of the present invention; and

[0027]FIGS. 31 and 32 are cross-sectional views illustrating a processof assembling the TFT array substrate and the organic EL substrateaccording to the third preferred embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0028] Reference will now be made in detail to preferred embodiments ofthe present invention, example of which is illustrated in theaccompanying drawings.

[0029] A configuration of an organic EL device according to thepreferred embodiment of the present invention will be explained througha process of manufacturing the organic EL device. In order tomanufacture the organic EL device, a TFT array substrate 500 in FIG. 15supplying a display power to the organic EL region and an organic ELsubstrate 900 in FIG. 17 including an organic EL region are respectivelymanufactured and then are assembled.

[0030] First, a process of manufacturing the TFT array substrate 500according to a first preferred embodiment of the present invention isexplained with reference to FIGS. 1 through 16 and 19, and a process ofmanufacturing the organic EL substrate 900 according to the firstpreferred embodiment of the present invention is explained withreference to FIG. 17. Thereafter, a process of assembling the TFT arraysubstrate and the organic EL substrate according to the first preferredembodiment of the present invention is explained with reference to FIGS.18 and 20.

[0031] In FIGS. 1, 3, 5, 7, 9, 11, 13, 15, left portions showcross-sectional views taken long line A-A of FIGS. 2, 4, 6, 8, 10, 12,14, 16, right portions show cross-sectional views taken long line B-B ofFIGS. 2, 4, 6, 8, 10, 12, 14, 16, respectively.

[0032] Referring to FIG. 19, in order to form one unit pixel on the TFTarray substrate 500 on a base substrate 400 in FIG. 1, two thin filmtransistors (TFTs) 100 and 200, a storage capacitor 300, gate lines 430supplying a bias voltage to turn on the TFTs, data lines 450 to which animage signal encoded from an image signal processing apparatus (e.g.,VGA card), and common power lines 460 are formed.

[0033] First, in order to manufacture the first TFT 100 and the secondTFT 200, as shown in FIGS. 1 and 2, a buffer layer 410 is formed on thewhole surface of the base substrate or the first insulating substrate400 to a predetermined thickness. The buffer layer 410 serves to preventthe first TFT 100, the second TFT 200, and the storage capacitor 300that will be formed in a subsequent process from ions coming from thebase substrate 400. For example, when the base substrate 400 is made ofglass, the buffer layer 410 prevents that ions such as Na⁺ and K⁺ ofglass are diffused into the first TFT 100, the second TFT 200, and thestorage capacitor 300.

[0034] An amorphous silicon layer is deposited on the buffer layer 410.Even though not shown, the amorphous silicon layer is subject to anannealing process, for example, a laser annealing, to form apolycrystalline silicon layer. The reason to form the polycrystallinesilicon layer is that the polycrystalline silicon layer has superiorelectron mobility to the amorphous silicon layer. Instead of depositingand annealing the amorphous silicon layer to form the polycrystallinesilicon layer, the polycrystalline silicon layer may be depositeddirectly on the buffer layer 410 through, for example, a chemical vapordeposition (CVD) technique. Therefore, the polycrystalline silicon layeris patterned into first and second semiconductor layers 110 and 210 ofan island shape.

[0035] In more detail, a photoresist is coated on the polycrystallinesilicon layer using, for example, a spin coating technique, and issubject to a light exposure to form photoresist patterns on a locationcorresponding to the first and second semiconductor layers 110 and 210.Using the photoresist patterns as a mask, the polycrystalline siliconlayer is wet- or dry-etched to form the first semiconductor layer 110and the second semiconductor layer 210. The photoresist patterns areremoved.

[0036] Subsequently, as shown in FIGS. 3 and 4, a gate insulating layer420 is formed over the whole surface of the base substrate to cover thefirst and the second semiconductor layers 110 and 210. The gateinsulating layer 420 serves to insulate the first and secondsemiconductor layers 110 and 210, respectively, from first and secondgate electrodes of the first and second TFTs 100 and 200 that will beformed in a subsequent process.

[0037] Thereafter, a first metal layer is deposited on the gateinsulating layer 420 using, for example, a sputtering technique to apredetermined thickness. The first metal layer comprises a metal such asaluminum (Al) and aluminum-neodymium alloy (Al:Nd). As shown in FIGS. 5,6 and 19 the first metal layer is patterned to form a first gateelectrode 120 of the first TFT 100, a second gate electrode 220 of thesecond TFT 200, a first capacitor electrode 310 of the storage capacitor300, and a gate line 430. Subsequently, an n-type or a p-type impurityis ion-implanted into the first and second semiconductor layers 110 and220 to form a first source region 130 and a first drain region 140 ofthe first TFT 100 and a second region 240 source and a second drainregion 230 of the second TFT 200.

[0038] In more detail, on a portion of the gate insulating layer 420corresponding to the first semiconductor layer 110, the first gateelectrode 120 having an area size smaller than the first semiconductorlayer 110 is formed. The gate line 430 is arranged in a transversedirection spaced apart from the first semiconductor layer 110 and isconnected to the first gate electrode 120. At this point, the firstsemiconductor layer 110 includes the source region 130 and the drainregion and 140, respectively, formed on both end portions thereof. Thefirst capacitor electrode 310 is formed between the first gate electrode120 and the second gate electrode 220 in such a way that it is spacedapart from the drain region 140 of the first semiconductor layer 110 andis connected to the second gate electrode 220. On a portion of the gateinsulating layer 420 corresponding to the second semiconductor layer210, the second gate electrode 220 having a smaller area size than thesecond semiconductor layer 210 is formed. At this point, the secondsemiconductor layer 210 includes the drain region 230 and the sourceregion 240, respectively, formed on both end portions thereof.

[0039] As shown in FIGS. 7 and 8, an interlayer insulator 440 is formedover the whole surface of the base substrate 400 to cover the first andsecond gate electrodes 120 and 220, and the first capacitor electrode310. The interlayer insulator 440 serves to insulate the first andsecond gate electrodes 120 and 220 from first source and drainelectrodes 182 and 184 and second source and drain electrodes 282 and284, which will be formed in a subsequent process. A portion of theinterlayer insulator 440 corresponding to the first capacitor electrode310 serves as a dielectric layer of the storage capacitor 300.

[0040] As shown in FIGS. 9 and 10, the interlayer insulator 440 includesa first source contact hole 172 and a first drain contact hole 174 and asecond drain contact hole 272 and source contact hole 274. The firstsource and drain contact holes 172 and 174 are formed at locationscorresponding to the first source and drain regions 130 and 140, and thesecond drain and source contact holes 272 and 274 are formed atlocations corresponding to the second drain and source regions 230 and240. The interlayer insulator 440 further includes a capacitor contacthole 320 at a location corresponding to a portion of the first capacitorelectrode 310 adjacent to the first drain region 140.

[0041] Subsequently, a second metal layer is deposited on the interlayerinsulator 440 using, for example, a sputtering technique. As shown inFIGS. 11, 12 and 19, the second metal layer is patterned to form a firstsource electrode 182 and a second drain electrode 184 of the first TFT100, a second source electrode 282 and a second drain electrode 284 ofthe second TFT 200, a second capacitor electrode 330 of the storagecapacitor 300, a data line 450, and a common power line 460.

[0042] The data line 450 is arranged in a perpendicular direction to thegate line 430 and is connected to one end portion of the first sourceelectrode 182. The other end portion of the first source electrode 182overlaps over one end portion of the first gate electrode 120. The firstsource electrode 182 is electrically connected to the first sourceregion 130 through first source contact hole 172. One end portion of thefirst drain electrode 184 overlaps over the other end portion of thefirst gate electrode 120, and the other end portion of the first drainelectrode 184 overlaps over an end portion of the first capacitorelectrode 310. The first drain electrode 184 is electrically connectedto the first drain region 140 and the first capacitor electrode 310,respectively, through the first drain contact hole 174 and the capacitorcontact hole 320. The common power line 460 is arranged in aperpendicular direction to the gate line 430 and is opposite to the dataline 450. The second capacitor electrode 330 is connected to the commonpower line 460 and overlaps the first capacitor electrode 310. Thesecond drain electrode 284 has one end portion overlapping over one endportion of the second gate electrode 220, and second source electrode282 has one end portion overlapping over the other end portion of thesecond gate electrode 220 and the other end portion extending from thecommon power line 460. The second drain electrode 284 is electricallyconnected to the second drain region 230 through the second draincontact hole 272, and the second source electrode 282 is electricallyconnected to the second source region 240 through the second sourcecontact hole 274.

[0043] Subsequently, as shown in FIGS. 13 and 14, a planarization film470 is formed over the whole surface of the base substrate 400 to coverthe first source and drain electrodes 182 and 184, the second source anddrain electrodes 282 and 284, the second capacitor electrode 330, thedata line 450, and the common power line 460. The planarization film 470includes a third drain contact hole 475 (see FIG. 15) at a locationcorresponding to a portion of the second drain electrode 284.

[0044] Finally, as shown in FIGS. 15 and 16, a conductive material layeris deposited on the planarization film 470 and is patterned to from aninterface pad 480. The interface pad 480 is electrically connected tothe second drain electrode 284 through the third drain contact hole 475.This completes the TFT array substrate 500.

[0045] The manufactured TFT array substrate 500 is then assembled withthe organic EL substrate 900.

[0046]FIG. 17 is a cross-sectional view illustrating the organic ELsubstrate 900 according to the first preferred embodiment of the presentinvention. First, a protection film 920 is formed on a transparentsubstrate or second insulating substrate 910. Preferably, the protectionfilm is made of SiO₂ or SiNx. The protection film 920 serves to shieldoxygen and moisture coming into through the transparent substrate 910.That is, the protection film 920 plays the same role as the conventionalmetal can. Thereafter, a transparent electrode 930 is deposited on theprotection film 920 to a predetermined thickness. Preferably, thetransparent electrode 930 is made of indium tin oxide or indium zincoxide. Subsequently, an organic EL layer 940 is formed on thetransparent electrode 930. The organic EL layer 940 includes one of ared organic EL material, a green organic EL material, and a blue organicEL material. Finally, a metal electrode 950 is formed on the organic ELlayer 940. Therefore, the organic EL substrate 900 according to thefirst preferred embodiment of the present invention is completed.

[0047]FIGS. 18 and 20 are cross-sectional views illustrating the organicEL device in which the TFT array substrate 500 is assembled with theorganic EL substrate 900 according to the first preferred embodiment ofthe present invention.

[0048] In order to assemble the TFT array substrate 500 and the organicEL substrate 900, for example, in a vacuum chamber (not shown), the TFTarray substrate 500 is aligned with the organic EL substrate 900 to facethe interface pad 480 of the TFT array substrate 500 toward the metalelectrode 950 of the organic EL substrate 900. Thereafter, an UV-curableagent 960 is coated on the_side of the TFT array substrate 500 and theorganic EL substrate 900 as shown in FIG. 20 and then is cured by anultraviolet ray. When the TFT array substrate 500 and the organic ELsubstrate 900 that the UV-curable agent is cured come out of the vacuumchamber, the TFT array substrate 500 and the organic EL substrate 900are closely stuck to each other due to a vacuum pressure, so that anelectric current can flow from the interface pad 480 of the TFT arraysubstrate 500 to the metal electrode 950 of the organic EL substrate900.

[0049]FIG. 21 is a perspective view illustrating a TFT array substrate500 according to a second preferred embodiment of the present invention.The TFT array substrate 500 includes a bump pad 490 in addition to aconfiguration of the TFT array substrate 500 of FIG. 16. At this point,the interface pad 480 is made of a conductive resin, a metal alloy, or aconductive metal such as Al, Pd, Au, Ti, TiW, NiCr, Cr, Nd, AlNd, andPt, and has a thickness of about 300 Å to about 20000 Å. The bump pad490 is formed using an electroplating technique, a non-electrolysisplating technique, a sputtering technique, a spin coating technique, ora chemical vapor deposition (CVD) technique. The bump pad 490 comprisesNi, Au, PbSn, In, or polymer.

[0050] The TFT array substrate 500 of FIG. 21 is assembled with aorganic EL substrate 600 in FIG. 25. FIGS. 22, 23, 24 and 25 arecross-sectional views illustrating a process of manufacturing theorganic EL substrate 600 according to the second preferred embodiment ofthe present invention.

[0051] First, as shown in FIG. 22, a transparent electrode is formed ona transparent substrate 610 to a predetermined thickness. Thetransparent electrode 620 is made of a transparent material such asindium tin oxide (ITO) or indium zinc oxide (IZO).

[0052] Thereafter, as shown in FIG. 23, an organic EL layer 630 isformed on the transparent electrode 620 using a shadow mask 640. Theorganic EL layer 630 includes one of a red organic EL material, a greenorganic EL material and a blue organic EL material. The shadow mask 640includes an opening portion 645. The opening portion 645 is formed at alocation corresponding to the organic EL layer 630.

[0053] Subsequently, as shown in FIG. 24, a conductive metal layer isdeposited on the organic EL layer 630 through the opening portion 655 ofthe shadow mask 650 to form a metal electrode 660.

[0054] As shown in FIG. 25, a protection film 670 is formed to overlapboth end portions of the metal electrode 660 using a photolithographytechnique, exposing an upper surface of the metal electrode 660.

[0055] Next, as shown in FIG. 26, an anisotropic conductive film (ACF)680 is formed over the whole surface of the transparent substrate 610 toa predetermined thickness. The anisotropic conductive film 680 has bothadhesive force and conductivity. In other words, the anisotropicconductive film 680 is configured in a way that conductive particles arefinely arranged among adhesive materials, and therefore, when theanisotropic conductive film 680 is pressurized, electrons can flowthrough the conductive particles. Such an anisotropic conductive film680 is used to enable an electric current to flow from one conductivematerial to another conductive material by an attachment method otherthan a soldering method.

[0056] The organic EL substrate 600 on which the anisotropic conductivefilm 680 is formed is aligned with the TFT array substrate 500 to facethe anisotropic conductive film 680 of the organic EL substrate 600toward the bump pad 490 of the TFT array substrate 500.

[0057] Then, as shown in FIG. 27, the TFT array substrate 500 and theorganic EL substrate 600 are heated, pressurized, and UV-treated to beglued to each other. As a result, not only the TFT array substrate 500and the organic EL substrate 600 are firmly stuck to each other, butalso electrons can travel from the bump pad 490 to the metal electrode660.

[0058] A portion of the anisotropic conductive film 680 where electronsdo not move serves to shield the organic EL device from oxygen andmoisture. That is, the portion of the anisotropic conductive film 680where a movement of electrons does not occur plays the same role as theconventional metal can.

[0059] When the TFT array substrate 500 and the organic EL substrate 600are assembled using the anisotropic conductive film 680, a much strongeradhesive force can be obtained than using the UV-curable agent 960 ofFIG. 20. In addition, electric characteristics can be improved byreducing such problems as a signal delay caused by a contact resistancebetween the interface pad 480 and the metal electrode 950 of FIG. 20.

[0060]FIGS. 28, 29 and 30 are cross-sectional views illustrating aprocess of manufacturing an organic EL substrate according to a thirdpreferred embodiment of the present invention. First, a transparentmaterial layer is deposited on a transparent substrate 710 and patternedto form a transparent electrode 720. Preferably, the transparentsubstrate 710 is made of glass, and the transparent electrode 720 ismade of indium tin oxide (ITO) or indium zinc oxide (IZO).

[0061] Thereafter, a polymer bump 730 is formed on the transparentelectrode 720. Preferably, the polymer bump 730 is made of photoresist,acryl, or polyimide. The polymer bump 730 is formed at a locationadjacent to a location 731 defined by a dotted line where an organic ELlayer will be formed in a subsequent process. The polymer bump 730 has ahigher height than a summation of a height of the organic EL layer and aheight of a metal electrode to be formed in subsequent process.

[0062] Subsequently, as shown in FIG. 29, a shadow mask 740 is alignedwith the array substrate so that the shadow mask 740 may be laid acrossthe polymer bump 730. The shadow mask 740 includes an opening portion745 that is somewhat wider in area size than the location 731, and aportion of the opening portion 745 of the shadow mask 740 is arranged ona portion of the polymer bump 730. Then, an organic EL material isdeposited on the transparent electrode 720 through the opening portion745 of the shadow mask to form an organic EL layer 750. The organic ELlayer 750 overlaps a portion of the polymer bump 730 and thus has a stepportion. The organic EL layer 750 has a somewhat larger area size thansubstantially needed.

[0063] Next, as shown in FIG. 30, a metal layer is deposited on theorganic EL layer 750 through the opening portion 745 of the shadow mask740 to form a metal electrode 760. The anode electrode 760 has the sameshape and area size as the organic EL layer 750.

[0064] Meanwhile, for the sake of a precise process, it is preferablethat the shadow mask 740 be as thin as possible. However, a thinnershadow mask tends to bend more. As a result, it is very difficult tosecure a pattern area of the organic EL layer 750 and the metalelectrode 760. For this reason, a portion of the shadow mask 740 is laidacross the polymer bumper 730.

[0065] As described above, a portion of the organic EL layer 750overlaps a portion of the polymer bump 730. This is to increase anadhesive force between the metal electrode 760 and the bump pad 490 andto prevent a short circuit between two adjacent metal electrodes withoutan additional protection film.

[0066] Subsequently, as shown in FIG. 31, an anisotropic conductive film770 is formed over the whole surface of the organic EL substrate 700 tocover the metal electrode 760. Then, the organic EL substrate 700 isaligned with the TFT array substrate 500 of FIG. 21 to face theanisotropic conductive film 770 of the organic EL substrate 700 towardthe bump pad 490 of the TFT array substrate 500.

[0067] Then, as shown in FIG. 32, the TFT array substrate 500 and theorganic EL substrate 700 are heated, pressurized, and UV-treated to beglued to each other. As a result, not only the TFT array substrate 500and the organic EL substrate 700 are firmly stuck to each other, butalso electrons can travel from the bump pad 490 to the metal electrode760.

[0068] As another example, a solder may be coated on the bump pad 490and then melted to solder the bump pad 490 of the TFT array substrate500 and the metal electrode 760 of the organic EL substrate 700.

[0069] As described herein before, using a method for manufacturing theorganic EL device according to the preferred embodiments of the presentinvention, an organic EL device having a high aperture ratio, a highluminance, and consuming less power can be obtained. In addition, anorganic EL device having a high reliability and a lightweight can beobtained.

[0070] While the invention has been particularly shown and describedwith reference to preferred embodiments thereof, it will be understoodby those skilled in the art that the foregoing and other changes in formand details may be made therein without departing from the spirit andscope of the invention.

What is claimed is:
 1. An organic EL device, comprising: a thin filmtransistor (TFT) array substrate including a first insulating substrate,a TFT and a capacitor formed on the first insulating substrate; and anorganic EL substrate including a second insulating substrate, atransparent electrode, an organic EL layer and a metal electrode,wherein the TFT is electrically connected to the metal electrode.
 2. Thedevice of claim 1, wherein the TFT array substrate further includes aconductive interface pad connected to the TFT, the conductive interfacepad directly contacting the anode electrode of the organic EL substrate.3. The device of claim 2, wherein the organic EL substrate furtherincludes a protection film that prevents external oxygen and moisturefrom permeating.
 4. The device of claim 3, wherein the protection filmis formed by depositing a SiNx layer and a SiO₂ layer at least once. 5.The device of claim 4, wherein the TFT array substrate and the organicEL substate are sealed by a UV-curable agent.
 6. The device of claim 1,wherein the TFT array substrate further includes a conductive interfacepad connected to the TFT and a conductive bump pad formed on theconductive interface pad, the conductive bump pad contacting the metalelectrode of the organic EL substrate by a conductive bonding agent. 7.The device of claim 6, wherein the conductive bonding agent is ananisotropic conductive film (ACF).
 8. The device of claim 7, wherein theanisotropic conductive film serves to prevent external oxygen andmoisture.
 9. The device of claim 1, wherein the TFT array substratefurther includes a conductive interface pad and a conductive bump padformed on the interface pad, and the organic EL substrate furtherincludes a polymer bump, wherein the conductive bump pad contacts aportion of the metal electrode corresponding to the polymer bump by aconductive bonding agent.
 10. The device of claim 9, wherein theconductive bonding agent is an anisotropic conductive film (ACF). 11.The device of claim 10, wherein the anisotropic conductive film servesto prevent oxygen and moisture from permeating through the secondinsulating substrate.
 12. The device of claim 1, wherein the transparentelectrode, the organic EL layer and the metal electrode are sequentiallystacked on the second insulating layer.
 13. A method for manufacturingan organic EL device, comprising steps of: providing a thin filmtransistor (TFT) array substrate including a TFT and a capacitor formedon a first insulating substrate; providing an orgnaic EL substrateincluding a transparent electrode, an organic EL layer and a metalelectrode; and sealing the TFT array substrate and the organic ELsubstrate to electrically connect the TFT of the TFT array substrate tothe metal electrode of the organic EL substrate.
 14. The method of claim13, wherein the TFT array substrate further includes a conductiveinterface pad connected to the TFT, the conductive interface paddirectly contacting the metal electrode of the organic EL substrate. 15.The method of claim 14, wherein the organic EL substrate furtherincludes a protection film that prevents external oxygen and moisturefrom permeating.
 16. The method of claim 15, wherein the protection filmis formed by depositing a SiNx layer and a SiO₂ layer at least once. 17.The method of claim 16, wherein the TFT array substrate and the organicEL substate are sealed by a UV-curable agent.
 18. The method of claim13, wherein the TFT array substrate further includes a conductiveinterface pad connected to the TFT and a conductive bump pad formed onthe conductive interface pad, the conductive bump pad contacting themetal electrode of the organic EL substrate by a conductive bondingagent.
 19. The method of claim 18, wherein the conductive bonding agentis an anisotropic conductive film (ACF).
 20. The method of claim 19,wherein the anisotropic conductive film serves to prevent externaloxygen and moisture from permeating through the second insulatingsubstrate.
 21. The method of claim 13, wherein the TFT array substratefurther includes a conductive interface pad and a conductive bump padformed on the interface pad, and the organic EL substrate furtherincludes a polymer bump, wherein the conductive bump pad contacts aportion of the metal electrode corresponding to the polymer bump by aconductive bonding agent.
 22. The method of claim 21, wherein theconductive bonding agent is an anisotropic conductive film (ACF). 23.The method of claim 22, wherein the anisotropic conductive film servesto prevent external oxygen and moisture from permeating through thesecond insulating substrate.
 24. The device of claim 13, wherein thetransparent electrode, the organic EL layer and the metal electrode aresequentially stacked on the second insulating layer.